1. Field of the Invention
The present invention relates to an automatic private branch exchange apparatus.
2. Description of the Prior Art
Hereinbelow, one type of conventional automatic private branch telephone exchange apparatus will be described with reference to FIGS. 4 and 5.
FIG. 4 is a block diagram showing a conventional automatic private branch telephone exchange apparatus having a casing 1. In the figure, broken lines represent sound communication lines, while solid lines represent control data lines, respectively.
In FIG. 4, numeral 16 denotes a main control section for controlling switching operations, such as, connection between extension lines 15a to 15c and office lines 8a to 8d, respectively, and between the extension lines mutually. Numeral 17 denotes a main storage section for storing data including managing data of the extension lines and the office lines and system managing data.
Symbol 2a denotes an office line control section connected to the office line 8a for communicating with the office line 8a. The office line control section 2a includes a communication passage control section 4 connected to the office line 8a for establishing a communication passage to carry a sound signal, such as, a voice signal, from the office line 8a to a communication passage switching section 9 when communicating with one of the extension or intercommunication lines 15a to 15c. The office line control section 2a further includes a dial signal sending section 3 which, in response to a dialing command from the main control section 16, generates and sends out a dial signal into the office line 8a via the communication passage control section 4. The office line control section 2a further includes a ring signal detecting section 5 for detecting a ring signal sent from a telephone exchange through the office line 8a and through the communication passage control section 4 upon occurrence of a call from a calling party and for notifying the main control section 16 of arrival of the call. The office line control section 2a further includes a response detecting section 6 for detecting a polarity inversion of the office line 8a which is indicative of an occurrence of response by a called party, that is, offhooking of a telephone handset at a side of the called party, and for notifying the main control section 16 of the response by the called party. The office line control section 2a further includes a termination-of-communication detecting section 7 for detecting a termination-of-communication signal formed by a DC hit (short break) signal indicative of a termination of communication at the side of a counter-party, that is, on-hooking of the telephone handset at the side of the counter-party, and sent from the telephone exchange through the office line 8a and through the communication passage control section 4 and for notifying the main control section 16 of the termination of communication.
Symbols 2b, 2c and 2d represent office line control sections connected to the office lines 8b, 8c and 8d, respectively. Each of the office line control sections 2b, 2c and 2d has the same structure as the foregoing office line control section 2a. Although only the four office line control sections 2a to 2d are shown for brevity of disclosure, further office line control sections are provided in practice.
Symbol 10a denotes an extension line control section connected to the extension line 15a for communicating with the extension line 15a. The extension line control section 10a includes a communication passage control section 12 connected to the extension line 15a for establishing a communication passage to carry a sound signal, such as, a voice signal, from the extension line 15a to the communication passage switching section 9 when communicating with one of the office lines 8a to 8d. The extension line control section 10a further includes a ring sound request sending section 11 for sending a ring sound request signal, as commanded by the main control section 16 upon occurrence of a call to the extension line 15a, into the extension line 15a via the communication passage control section 12. The extension line control section 10a further includes a dial signal receiving section 13 for detecting a dial signal sent from an extension telephone set (not shown) connected to the extension line 15a through the communication passage control section 12 and for notifying the main control section 16 of the detected dial signal. The extension line control section 10a further includes an on/off-hook detecting section 14 for monitoring an off-hook signal sent from the extension telephone set through the communication passage control section 12 so as to notify the main control section 16 of on/off-hook information.
Symbols 10b and 10c represent extension line control sections connected to extension lines 15b and 15c, respectively, Each of the extension line control sections 10b and 10c has the same structure as the foregoing extension line control section 10a. Although only the three extension line control sections 10a to 10c are shown for brevity of disclosure, further extension line control sections are provided in practice.
The communication passage switching section 9 achieves connection, under the control of the main control section 16, between the extension line control sections 10a to 10c and the office line control sections 2a to 2d, respectively, and between the extension line control sections mutually.
An operation of the conventional private branch telephone exchange apparatus having the foregoing structure will be described hereinbelow, wherein a call is made from the extension telephone set connected to the extension line to a called party through the office line.
When, for example, an operator offhooks the extension telephone set connected to the extension line 15a, the on/off-hook detecting section 14 of the extension line control section 10a receives an off-hook signal and notifies it to the main control section 16. In response to this notification, the main control section 16 is set ready to receive a dial signal from the dial signal receiving section 13 of the extension line control section 10a.
Thereafter, when the operator inputs dialing data, the main control section 16 receives the corresponding dial signal from the dial signal receiving section 13 of the extension line control section 10a and identifies the received dial signal. The main control section 16, then, monitors the office line control sections 2a to 2d so as to detect one which is vacant, that is, not used. It is assumed that the office line control section 2a is vacant. Subsequently, the main control section 16 sends the dialing data to the dial signal sending section 3 of the detected office line control section 2a. In response to receipt of the dialing data, the dial signal sending section 3 executes calling to the office line 8a based on the received dialing data, that is, produces the dial signal based on the received dialing data and sends it out into the office line 8a.
Now, the operation of the main control section 16 when performing the calling through the office lines will be described in further detail with reference to a state transition diagram shown in FIG. 5.
Initially, the main control section 16 is in an extension-line stand-by state (20) for awaiting the off-hook signal from any of the on/off-hook detecting sections 14 of the extension line control sections 10a to 10c.
When the off-hook notification (21) is received from any of the on/off-hook detecting sections 14, the main control section 16 shifts to a dial-tone state (22) for sending a dial tone to the corresponding extension telephone set through the extension line. During the dial-tone state (22), when the on-hook notification (23) is received from the on/off-hook detecting section 14, the main control section 16 returns to the extension-line stand-by state (20).
On the other hand, when the dial signal (24) Is received, during the dial-tone state (22), from the dial signal receiving section 13, the main control section 16 monitors the office line control sections 2a to 2d so as to detect one which is vacant, that not used. It is assumed that the office line control section 2a is vacant.
Subsequently, the main control section 16 controls the office line control section 2a to catch the corresponding office line 8a (25), that is, to close a direct current loop to connect the office line 8a, so that the main control section 16 shifts to a calling state (27) where the calling is executed to the office line 8a.
On the other hand, when none of the office lines 8a to 8d are caught (26), that is, none of the office line control sections 2a to 2d are available, the main control section 16 shifts to a busy-tone state (31) for sending a busy tone to the extension telephone set via the extension line 15a.
During the calling state (27) or the busy-tone state (31), when the on-hook notification (28) or (32) is received from the on/off-hook detecting section 14, the main control section 16 returns to the extension-line stand-by state (20). On the other hand, during the calling state (27), when the dial signal (30) is fully sent to and received by the telephone exchange and further when a line response (29) occurs, that is, when the office line 8a is Inverted in polarity, the main control section 16 shifts to a communication state (33) for establishing a communication between the extension line 15a and the office line 8a.
Recently, companies have been putting great importance on the telemarketing. The telemarketing is, in general, performed through telephone based on a customer list in the form of a data base, for example, the Introduction of merchandise, the telephone research for election and the like. In the telemarketing, some operators make calls In sequence according to the customer list of the data base.
However, when the telemarketing is performed using the foregoing conventional private branch exchange apparatus, each operator should also perform those things other than conversation with the called party, including, such as, dialing, waiting, judging whether the called party is in communication with another or whether the called party is absent, and the like. Accordingly, a time is largely required for other than conversation with the called party so as to lower the efficiency of the telemarketing. Particularly, when the called party does not offhook the telephone handset, such as, when the called party is absent, the operator has to judge absence of the called party after hearing ring back tones several times so that the efficiency of the telemarketing is seriously lowered.